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1.
Rats undergoing extinction of lever-pressing for food after the attenuation of an external feedback for this behavior exhibit excessive lever-pressing unaccompanied by an attempt to collect a reward. This behavior may be analogous to the excessive and unreasonable behavior seen in obsessive-compulsive disorder. In the present study, we tested the hypothesis that the compulsive behavior induced by signal attenuation is mediated via D(1) rather than D(2) receptors. Administration of 0.005, 0.01 and 0.03 mg/kg of the D(1) antagonist SCH 23390 reduced the number of compulsive lever-presses without affecting the number of lever-presses followed by an attempt to collect a reward. In contrast, administration of 0.005, 0.01, 0.024, 0.036 and 0.05 of the D(2) antagonist haloperidol dose-dependently decreased both types of lever-presses. In addition, haloperidol at doses that decreased lever-pressing in the post-training signal attenuation procedure (0.036 and 0.05 mg/kg) had a similar effect in regular extinction, whereas an SCH 23390 dose that decreased compulsive lever-pressing in the post-training signal attenuation procedure (0.01 mg/kg) had no effect on regular extinction. On the basis of electrophysiological data on the response of dopamine neurons to the omission of an expected reward, these results were interpreted as suggesting that compulsive lever-pressing depends on a phasic decrease in the stimulation of D(1) receptors. The implications of these results for the pathophysiology and treatment of obsessive-compulsive disorder are discussed. 相似文献
2.
Twenty-eight patients participated prospectively in a study to evaluate the impact of hysteroscopically detected uterine and cervical anomalies on the success rate of ET in an IVF-ET program. All participants had a normal intrauterine cavity by standard HSG. All the patients had a diagnostic office hysteroscopy under paracervical block before commencing COH. Because our IVF program does not include hysteroscopy as a requirement before undergoing IVF and because the significance of mild intrauterine abnormalities is not yet known, the hysteroscopic findings were not relayed to the personnel involved in the IVF-ET procedure. Sixteen patients (group I) had a normal hysteroscopic evaluation. Twelve patients (group II) had abnormal hysteroscopic findings including small uterine septa, small submucous fibroids, uterine hypoplasia and cervical ridges. Although no difference in patients or cycle characteristics was present, there was a significant difference in the clinical PR between patients in groups I and II. In conclusion, in an IVF-ET program patients with normal hysterography but abnormal hysteroscopic findings had a significantly lower clinical PR, demonstrating the importance of performing hysteroscopy before IVF-ET. 相似文献
3.
E. Stermer J. Bejar† I. Miselevich† O. Goldstein D. Keren A. Lavy J. H. Boss† D. Keren 《Colorectal disease》2005,7(4):345-349
BACKGROUND: Total excision of colonic polyps is not always attainable and in some patients it is clinically contraindicated. Also, a resected polyp may be lost at any step between its endoscopic removal and its embedding in paraffin. The aim of this study was to compare the histological features of colonic polyps as analysed by the study of biopsy-forceps obtained samples with those assessed on scrutinizing the totally resected growths. PATIENTS AND METHODS: This prospective study included a cohort of 59 patients in whom, in the course of an elective colonoscopy, a total excision of a 6 mm-sized or larger polyp was called for. Sizeable biopsies were obtained by means of an Olympus Multibyte forceps prior to the total polypectomy. Subsequent to the study of the polypectomy specimens, the forceps biopsy samples were submitted for histological examination. The pathologists were blinded as to the source of the tissue they were studying. The diagnoses rendered by evaluating the biopsy samples and polypectomy specimens of each patient were contrasted with each other. RESULTS: Major discrepancies between the histological features of the fragments captured by the biopsy-forceps and the factual nature of the totally removed polyps were uncovered in 11 (18.6%) of 59 cases. Intriguingly, the grade of the tumours was underrated in all the 11 cases, as judged by contrasting the tentative diagnoses of the forceps-biopsies with the decisive diagnoses of the polypectomies. Importantly, 2 adenocarcinomas would have been missed by just looking at the forceps-retrieved sample. CONCLUSIONS: In our experience, a discordance of 18.6% is to be expected between the diagnoses rendered after examining forceps-biopsies of and totally excised colonic polyps. Nevertheless, it is advisable to procure biopsies prior to the excision of the growths, because on those occasions in which patients' growths cannot be removed or have not been retrieved for one reason or another, a small forceps-captured tissue sample correctly reflects the characteristics of the polyp in 81.4% of the cases. Finally, the biopsies may be discarded in the event that total removal was successful. 相似文献
4.
Daphna Oyserman PhD Rami Benbenishty PhD Dalia Ben-Rabi MSW 《Child psychiatry and human development》1992,22(3):199-211
This study provides an overview of children, their families, and their circumstances at the time that the child entered foster care in Israel. Data regarding a representative sample of 800 children were collected as part of the ongoing operation of a clinical information system set up for Israel's foster care service in 1988. Implications of our findings for interventions are discussed. 相似文献
5.
Daphna Mezad Mordechai Hallak Mahmoud Huleihel Limor Gortzak-Uzan Ana Smolin Moshe Mazor 《Magnesium research》2002,15(3-4):247-252
Our objective was to evaluate the effect of intravenous magnesium sulphate administration to patients with preterm labour on maternal serum and amniotic fluid IL-1beta, IL-6, IL-10 and TNFalpha concentrations. Thirty-six patients at 24-34 weeks of singleton gestation, who presented with contractions (> or = 8 in 60 min) had amniocentesis to rule out intrauterine infection. The patients received intravenous MgSO4 for tocolysis. Twenty-six patients had amniocentesis performed before initiation of MgSO4 (controls) while 10 others had the procedure during tocolytic therapy (study patients). Magnesium, IL-1beta, IL-6, TNFalpha and IL-10 concentrations were measured. Study and control groups were statistically compared using Student t test. Mean magnesium levels were significantly higher in the study group (P < 0.01). There were no significant differences between the cytokines levels in maternal serum and in amniotic fluid between the groups. Our results suggest that the mechanism of magnesium as a tocolytic agent may not be mediated via the examined cytokines. 相似文献
6.
Marjorie C. Feinson Yaacov Lerner Daphna Levinson & Miriam Popper 《The Milbank quarterly》1997,75(2):235-260
Untested assumptions concerning ambulatory treatment have shaped mental health policies for decades. Three opinions prevail: (1) all use is alike; (2) any use leads to high use; and (3) all high use is discretionary and therefore excessive. These assumptions were tested, using data from a nationwide survey of ambulatory utilizers in Israel, a country that has universal coverage. The findings, based on detailed clinical and treatment records, challenge all three assumptions. Moreover, they document a diversity of clinical needs while also verifying substantial variations in the type, frequency, and duration of treatment provided to meet those needs. In brief, Israeli data do not confirm continuing concerns by policy makers about uncontrollable use of services with expanded mental health coverage. Special policy limitations on mental health treatment should be reconsidered in light of empirical evidence from a system without the restrictions that exist in the United States. 相似文献
7.
The effect of synthetic progestins found in oral contraceptives has potential implications for developing embryos in women who receive oral contraceptives during early pregnancy. We assessed the effect of the progestin norgestrel on the developing pre-embryo. B3C6F1 mice were given 5 IU PMSG followed by 5 IU hCG 48h later. Studies were performed on pre-embryos recovered and pooled at both 24h (Group A) and 48h (Group B) post hCG. At each time period, they were randomly assigned to control or norgestrel (4.0 ng/ml) treatment. In a third study, pre-embryos collected 24h post hCG were cultured in the absence or presence of 8.0, 80.0, or 800 ng/ml norgestrel. Cultures were performed in Ham's F-10 media with 10% fetal calf serum at 37 degrees C in an atmosphere of 5% CO2, 5% O2 and 90% N2 with 15-30 embryos per 1 ml of culture fluid. At 24h, 48h and 72h post recovery, cultures were viewed, the appearance of embryos noted, and number of blastomeres recorded. Compared to control groups, analysis demonstrated no significant difference in the rate of development of control and norgestrel pre-embryos in any group at any time period (24h, 48h, or 72h post recovery). We conclude that norgestrel at the dose tested has no acute adverse morphological effects on development of mouse pre-embryos. This observation has potential clinical implications with regard to inadvertent use of norgestrel-containing oral contraceptives during early days of pregnancy, as well as consideration of the mechanism of action of norgestrel-containing "morning after" pills. 相似文献
8.
This paper analyzes the effect of quality and accessibility of health services and other public infrastructure on the health of children in Ghana. We focus on child survival, child height and weight using data from the Ghana Living Standards Survey. The results suggest an important role for public health policy in eliminating the rural-urban disparities in health status and particularly in improving the health status of rural children and reducing their mortality rates. Increased availability of birth services and other related child programs, as well as Improved water and sanitation infrastructure would have an immediate payoff. 相似文献
9.
T. R. Nunn M. Etsub T. Tilahun R. O. E. Gardner V. Allgar A. M. Wainwright C. B. D. Lavy 《Strategies in trauma and limb reconstruction (Online)》2018,13(3):171-177
The aim of the study was to develop a simple and reliable clinical scoring system for delayed presenting clubfeet and assess how this score predicts the response to Ponseti casting. We measured all elements of the Diméglio and the Pirani scoring systems. To determine which aspects were useful in assessing children with delayed presenting clubfeet, 4 assessors examined 42 feet (28 patients) between the ages of 2–10 years. Selected variables demonstrating good agreement were combined to make a novel score and were assessed prospectively on a separate consecutive cohort of children with clubfeet aged 2–10, comprising 100 clubfeet (64 patients). Inter-observer and intra-observer agreement was found to be greatest using the following clinically measured angles of the deformities. These were plantaris, adductus, varus, equinus of the ankle and rotation around the talar head in the frontal plane (PAVER). Measured angles of 1–20, 21–45 and?>?45 degrees scored 1, 2 and 3 points, respectively. The PAVER score was derived from both the sum of points derived from measured angles and a multiplier according to age. The sum of the points was multiplied with 1, 1.5 or 2 for ages 2–4, 5–7 and 8–10, respectively. This demonstrated a good association with the total number of casts to achieve a full correction (tau?=?0.71). A score greater than 18 out of 30 indicated a cast-resistant clubfoot. The score could be used clinically for prognosis and treatment, and for research purposes to compare the severity of clubfoot deformities. 相似文献
10.
Suissa A Yassin K Lavy A Lachter J Chermech I Karban A Tamir A Eliakim R 《Hepato-gastroenterology》2005,52(62):352-355
BACKGROUND/AIMS: ERCP has been used since 1968 both as a diagnostic and as a therapeutic procedure. In the last ten years several less invasive imaging methods have developed which allow visualization of bile ducts and pancreatic ducts; therefore ERCP has become mainly a therapeutic tool. The aim of the study was to prospectively evaluate the early outcome of ERCP when used essentially as a therapeutic tool. METHODOLOGY: All patients referred to our unit between April 1 1998 and March 31 2000 were included in the study. The indication for the procedure, number of cannulations, duration of procedure, performance of endoscopic sphinterotomy or pre-cut, insertion of stent and the final outcome were recorded. All patients were visited (in-patients) or contacted by phone (outpatients) 24 hours and one week after the procedure. If a complication occurred the patient was followed until it was resolved. RESULTS: 722 ERCP procedures were performed on 534 patients (59% females), mean age 63.4 years (range 3 to 98 years). The procedure was performed with a therapeutic intention in 95% of cases because of suspicion of: cholelithiasis (58%), tumor of pancreas/bile ducts (30%), post-cholecystectomy bile leak or bile duct stenosis (6%) or treatment of chronic pancreatitis (1%). The overall success rate of selective duct cannulation was 92%. Endoscopic sphincterotomy was performed in 375 procedures (52%), pre-cut in 152 (21%) and stent inserted in 180 (25%). Among the 701 procedures with complete information 76 complications occurred in 73 patients (10.8%): pancreatitis 4.3%, perforation 1.3%, sepsis 3.7%, bleeding 1.4%. Most of the complications (63/701, 9%) were mild to moderate. Procedure-related mortality was 0.6% due to perforation (1 patient), and sepsis (3 patients). The main factors influencing the complication rate were the difficulty of the examination, performance of an invasive procedure or the operator. CONCLUSIONS: In the era of therapeutic ERCP, the risk of severe complication from the procedure is low--1.8% (including a mortality rate of 0.6%) when using the appropriate technique in experienced and skilled hands. 相似文献